U.S. patent application number 16/329109 was filed with the patent office on 2019-07-25 for downhole cutting tool and method of use.
The applicant listed for this patent is ARDYNE HOLDINGS LIMITED. Invention is credited to Steffen Hansen.
Application Number | 20190226294 16/329109 |
Document ID | / |
Family ID | 57139752 |
Filed Date | 2019-07-25 |
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United States Patent
Application |
20190226294 |
Kind Code |
A1 |
Hansen; Steffen |
July 25, 2019 |
Downhole Cutting Tool and Method of Use
Abstract
A downhole cutting tool and method of operating the cutting
tool. The cutting tool (10) has first and second flow pathways
through the tool body (12) and a switching mechanism operated by
axial force via weight-set or drop ball to control the opening of
the flow pathways and direct fluid to the second flow path and
operate the cutting mechanism (18). Fluid flow through the first
pathway can be used to actuate a hydraulically operated tool
mounted on the tool string below the cutting tool (10).
Inventors: |
Hansen; Steffen; (Aberdeen,
Aberdeenshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ARDYNE HOLDINGS LIMITED |
Aberdeen Aberdeenshire |
|
GB |
|
|
Family ID: |
57139752 |
Appl. No.: |
16/329109 |
Filed: |
September 6, 2017 |
PCT Filed: |
September 6, 2017 |
PCT NO: |
PCT/GB2017/052588 |
371 Date: |
February 27, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E21B 29/005 20130101;
E21B 10/322 20130101; E21B 23/04 20130101 |
International
Class: |
E21B 23/04 20060101
E21B023/04; E21B 29/00 20060101 E21B029/00; E21B 10/32 20060101
E21B010/32 |
Foreign Application Data
Date |
Code |
Application Number |
Sep 7, 2016 |
GB |
1615222.5 |
Claims
1-69. (canceled)
70. A downhole cutting tool comprising: a mandrel, the mandrel
having a central mandrel bore with a first end configured to be
coupled to an upper tool string, and a first set of ports at a
second end; a tool body, the tool body comprising a cutting
mechanism having a plurality of knives to cut casing, and having a
first end surrounding a portion of the mandrel and a second end
configured to be coupled to a lower tool string; a piston axially
moveable in a chamber of the tool body and comprising a piston
sleeve with a shoulder configured to engage a pivot arm of the
cutting mechanism, a piston inlet nozzle to a central piston bore
and ports extending into the central piston bore; a first flow
pathway through the tool body; a second flow pathway through the
tool body; the downhole cutting tool being switchable between a
first position and a second position, wherein: in the first
position: the first flow pathway is open, and fluid flow from the
upper tool string enters the central mandrel bore, passes through
the first set of ports into a bypass channel to enter the ports
extending into the central piston bore and to an inner bore of the
lower tool string, and the knives are retracted and held in a
storage position; and in the second position: the second flow
pathway is open, the first flow pathway is closed as the bypass
channel is closed, and fluid flow from the upper tool string enters
the central mandrel bore, passes into the chamber to enter the
inlet nozzle to the central piston bore and move the piston sleeve
to engage the shoulder with the pivot arm to rotate the knives to
an extended operational position to cut casing.
71. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool includes shear screws to hold the mandrel
relative to the tool body in the first position and weight is set
down to move the mandrel relative to the tool body to the second
position.
72. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool includes a drop ball seat at the second end
of the mandrel and a drop ball is used to move the mandrel relative
to the tool body to the second position.
73. The downhole cutting tool claim 70 wherein the downhole cutting
tool further comprises a third flow pathway configured to direct at
least some fluid flow into an annular space around the tool.
74. The downhole cutting tool according to claim 73 wherein the
third flow pathway is via a second set of ports, at the second end
of the mandrel axially spaced from the first set of ports, and
further ports on the tool body.
75. The downhole cutting tool according to claim 74 wherein the
downhole cutting tool further comprises a port valve, the port
valve blocking the second set of ports when the downhole cutting
tool is in the second position.
76. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool further comprises spring activated keys
located on an internal surface of the tool body which engage with
grooves located on an outer surface of the mandrel to hold the
mandrel in the first position.
77. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool includes a drop ball seat at the second end
of the mandrel between the first set of ports and a second set of
ports with the second set of ports having channels to direct fluid
passed the first set of ports to the channel at the second end of
the mandrel so that a drop ball will switch the downhole cutting
tool between the first and second positions.
78. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool further comprises biasing means to bias the
piston in the first position and the biasing means is selected from
a group comprising: spring, compression spring, compressible member
and resilient member.
79. The downhole cutting tool according to claim 70 wherein the
cutting mechanism further comprises a flow restriction assembly
axially moveable in the tool body and located in the chamber
between the second end of the mandrel and the piston.
80. The downhole cutting tool according to claim 79 wherein the
flow restriction assembly comprises an inlet nozzle, a bore and an
outlet wherein the outlet is configured to seat in the piston inlet
nozzle.
81. The downhole cutting tool according to claim 80 wherein the
inlet nozzle is smaller than the piston inlet nozzle.
82. The downhole cutting tool according claim 70 wherein the tool
body has a spline so as to transfer torque through the downhole
cutting tool in the first and second mandrel positions.
83. The downhole cutting tool according to claim 70 wherein the
downhole cutting tool comprises a tool string coupled to the
downhole cutting tool as the upper tool string and the lower tool
string and wherein a hydraulically actuated downhole tool is
coupled to the lower tool string.
84. The downhole cutting tool according to claim 83 wherein the
hydraulically actuated downhole tool is selected from a group
comprising: drill, mill, packer, bridge plug, hydraulic
disconnects, whipstock, hydraulic setting tools and perforating
gun.
85. A method of operating a downhole cutting tool and a
hydraulically actuated downhole tool on a single downhole trip
comprising: providing a downhole cutting tool according to claim 70
wherein the downhole cutting tool comprises a tool string coupled
to the downhole cutting tool as the upper tool string and the lower
tool string and wherein a hydraulically actuated downhole tool is
coupled to the lower tool string.; running the tool string into
casing with the downhole cutting tool in the first position;
pumping fluid through the downhole cutting tool via the first flow
pathway to actuate the hydraulically actuated downhole tool;
switching the downhole cutting tool to the second position; pumping
fluid through the downhole cutting tool via the second flow pathway
to extend the knives and thereby cut the casing.
86. The method of operating a downhole cutting tool and a
hydraulically actuated downhole tool on a single downhole trip
according to claim 85 wherein the method comprises setting weight
down on the downhole cutting tool to switch it to the second
position.
87. The method of operating a downhole cutting tool and a
hydraulically actuated downhole tool on a single downhole trip
according to claim 85 wherein the method comprises dropping a ball
through the tool string to switch the downhole cutting tool to the
second position.
88. The method of operating a downhole cutting tool and a
hydraulically actuated downhole tool on a single downhole trip
according to claim 85 wherein the method comprises rotating the
downhole cutting tool by rotating the tool string whilst the knives
are deployed to cut the casing.
89. The method of operating a downhole cutting tool according to
claim 85 wherein the hydraulically actuated downhole tool is a
drill and actuation of the drill is used to dress-off a cement plug
prior to cutting the casing.
Description
[0001] The present invention relates to a downhole tool and method
of use, and in particular to downhole tubular cutting tool. A
particular aspect of the invention relates to a tool string
comprising a cutting tool and at least one other downhole tool.
BACKGROUND TO THE INVENTION
[0002] During well construction, a hole is drilled to a
pre-determined depth and a casing is run into the well. Cement is
pumped down the casing and is displaced up the annulus between the
casing and the original wellbore. The purpose of the cement is to
secure the casing in position and ensure that the annulus is
sealed.
[0003] Over time, which may be several decades, the production of
hydrocarbons reduces until the production rate of the well is no
longer economically viable, at which point the well has reached the
end of its productive life. The well is plugged and abandoned.
[0004] Typically to abandon the wellbore a cement plug is placed in
the wellbore casing to seal the wellbore casing annulus. It is
known to use downhole casing cutters lowered into the casing to cut
the casing above the cement plug and to remove the severed casing
section from the wellbore. This task involves multiple trips
downhole.
[0005] Other downhole tools must be lowered into the casing to
allow a range of downhole tasks to be performed including drills or
milling tools to extend the wellbore or dress-off cement plugs and
packers to seal the wellbore.
[0006] Often a number of downhole tasks must be completed which
require multiple trips downhole to perform each task. This can be a
time consuming and expensive process requiring the tool string to
be returned to surface to change out the downhole tool for each
specific task.
SUMMARY OF THE INVENTION
[0007] It is an object of an aspect of the present invention to
obviate or at least mitigate the foregoing disadvantages of prior
art downhole tools.
[0008] It is another object of an aspect of the present invention
to provide a robust, reliable and compact downhole cutting tool
suitable for use on a tool string.
[0009] It is a further object of an aspect of the present invention
to provide a tool string with a downhole cutting tool and at least
one other downhole tool capable of performing a range of downhole
tasks with improved productivity and efficiency.
[0010] Further aims of the invention will become apparent from the
following description.
[0011] According to a first aspect of the invention there is
provided a downhole cutting tool comprising:
[0012] a tool body;
[0013] a first flow pathway through the tool body;
[0014] a second flow pathway through the tool body;
[0015] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway and
[0016] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway.
[0017] By providing a tool capable of controlling the opening of
the fluid flow paths in the downhole cutting tool it may allow the
controlled actuation of the cutting tool and at least one other
tool on the same tool string. This may facilitate multiple downhole
operations to be performed on a single trip.
[0018] Preferably the switching mechanism may be operable to
control the opening of the first and/or second fluid flow pathway
in response to an axial force. The switching mechanism may be
operable to control the opening of the first and/or second fluid
flow pathway in response to an axial force acting on the switching
mechanism and/or tool body.
[0019] The switching mechanism may be actuated by a set-down weight
and/or a drop ball.
[0020] Preferably the switching mechanism comprises a mandrel which
is configured to be axial moveable relative to the tool body. The
mandrel may be axially moved from a first position to a second
position in response to an axial force. The mandrel may be axially
moved from a first position to a second position in response to an
axial force acting on the mandrel.
[0021] The mandrel may have a first set of ports and a second set
of ports in fluid communication with the mandrel bore and/or tool
string bore.
[0022] The first set of ports may be in fluid communication with
the first fluid flow pathway. The second set of ports may be in
fluid communication with the second fluid flow pathway.
[0023] The mandrel may be configured to move the first set of ports
between a first position where they are in fluid communication with
the first fluid flow pathway and a second position where they are
not in fluid communication with the first fluid flow pathway.
[0024] The mandrel may be configured to move the second set of
ports between a first position where they are not in fluid
communication with the second fluid flow pathway and a second
position where they are in fluid communication with the second
fluid flow pathway.
[0025] Preferably the mandrel is configured to be moved between a
first position where the first set of ports are not in fluid
communication with the first fluid flow pathway and the second set
of ports are in fluid communication with the second fluid flow
pathway in response to an axial force.
[0026] Preferably the mandrel is configured to be moved to a
position where the first set of ports are in fluid communication
with the first fluid flow pathway and the second set of ports are
not in fluid communication with the second fluid flow pathway when
the axial force is removed.
[0027] The switching mechanism may comprise a drop ball seat.
[0028] The axial force may be applied to the switching mechanism by
a set down weight and/or a ball drop. This may allow the tool to
perform a number of downhole tasks in a single trip without having
to return to surface or perform multiple trips.
[0029] The tool may comprise a third fluid flow path configured to
direct at least some fluid flow into the annular space around the
tool.
[0030] By directing at least part of the fluid flow into the
annular space around the tool it may allow fluid flow to cool a
tool on the tool string such as drilling tools. It may allow
cuttings and debris to be washed away from cutting sites.
[0031] By providing a switching mechanism the tool in response to
an axial force may switch the flow regime in the tool. The tool may
have an initial flow pathway where the fluid flow passes through
the tool to actuate a tool on the same tool string, and the
switching mechanism in response to an axial force switches the tool
to a second flow pathway where flow through the second flow pathway
actuates the cutting mechanism.
[0032] A further benefit of this system is that different downhole
tools with specific hydraulic actuation flow rates may be
controlled on the same tool string. Drill tools and milling tools
that require a high flow rate may be located beneath the cutter
tool on the tool string and may be independently controlled.
[0033] The first flow pathway and/or second flow pathway may be
open before an axial force is applied to the switching mechanism.
The first flow pathway and/or second flow pathway may be closed
before an axial force is applied to the switching mechanism.
[0034] The switching mechanism may be configured to open the first
pathway and close or partially close the second pathway in response
to an axial force. The switching mechanism may be configured to
open the second pathway and close or partially close the first
pathway in response to an axial force.
[0035] The switching mechanism may be configured to selectively
open one of the first or the second fluid flow pathways.
[0036] The first flow pathway may be configured to bypass the
cutting mechanism.
[0037] The cutter mechanism comprises at least one extendable
cutter. The cutter may comprise at least one blade or knife.
Preferably the cutting mechanism comprises a plurality of cutters.
The plurality of cutters may be circumferentially disposed about a
section of the downhole tool.
[0038] The cutting tool may comprise a sleeve piston configured to
be slidably mounted within the tool body. The sleeve position may
be configured to move the cutters between a storage position where
the cutters are retracted and do not engage the casing and an
operational position where the cutters are extended and engage the
casing.
[0039] The piston may be configured to move between a first
position and a second position. In the first position the position
may retain the at least one cutter in retracted position. The
piston may be configured to move the cutters to an extended
operation position when the piston is in the second position. The
piston may comprise a shoulder. The shoulder may be configured to
engage the at least one cutter.
[0040] The first flow pathway may be configured to bypass or
partially bypass the piston.
[0041] The cutting mechanism may be hydraulically actuated.
Preferably the cutting mechanism is actuated by directing fluid
into the second fluid flow path. The cutting mechanism may be
configured to move in response to fluid pressure acting on the
sleeve piston.
[0042] The cutting mechanism may be configured to be actuated in
response to fluid flow in the second fluid flow pathway.
[0043] The cutting mechanism may comprise a flow restriction
assembly. The flow restriction assembly may comprise a nozzle. The
nozzle may be configured to introduce a pressure difference in the
fluid upstream of the nozzle and the fluid downstream of the
nozzle. The nozzle may be dimensioned to provide resistance to
fluid flowing into nozzle. The restriction assembly and/or the
piston sleeve may be configured to move axially when fluid acts on
the nozzle. The restriction assembly and/or the piston sleeve may
be configured to move axially when fluid above a predetermined
threshold flows through the second pathway and acts on the
nozzle.
[0044] The piston may comprise a nozzle. The nozzle on the piston
may be larger than the nozzle on the restriction assembly.
[0045] Preferably axial movement of the restriction assembly and/or
the piston sleeve when fluid flows through the second pathway
deploys the cutters.
[0046] The downhole cutting tool may comprise a tool string coupled
to a downhole tool. The downhole cutting tool may comprise a tool
string coupled to a hydraulically actuated downhole tool. The
downhole cutting tool may comprise a tool string coupled to a
series of hydraulically actuated downhole tools.
[0047] The hydraulically actuated downhole tool may be selected
from a drill, mill, packer, bridge plug, hydraulic disconnects,
whipstock, hydraulic setting tools or perforating gun.
[0048] According to a second aspect of the invention there is
provided a downhole cutting tool comprising:
[0049] a tool body;
[0050] a first flow pathway through the tool body;
[0051] a switching mechanism configured to open a second flow
pathway through the tool body and;
[0052] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway.
[0053] Preferably the switching mechanism is configured to open a
second flow pathway through the tool body in response to an axial
force.
[0054] The cutting mechanism may be configured to be actuated in
response to fluid flow in the second fluid flow pathway.
[0055] The cutting mechanism may be configured to be actuated in
response to fluid flow above a threshold flow rate in the second
fluid flow pathway.
[0056] Embodiments of the second aspect of the invention may
include one or more features of the first aspect of the invention
or its embodiments, or vice versa.
[0057] According to a third aspect of the invention there is
provided a downhole cutting tool comprising:
[0058] a tool body;
[0059] a first flow pathway through the tool body;
[0060] a second flow pathway through the tool body;
[0061] a cutting mechanism configured to be actuated in response to
fluid flow in the second fluid flow pathway and
[0062] a switching mechanism configured to selectively open one of
the first or the second fluid flow pathways in response to an axial
force
[0063] Embodiments of the third aspect of the invention may include
one or more features of the first or second aspect of the invention
or their embodiments, or vice versa.
[0064] According to a fourth aspect of the invention there is
provided a tool string comprising
[0065] a downhole cutting tool comprising:
[0066] a tool body
[0067] a first flow pathway through the tool body;
[0068] a second flow pathway through the tool body;
[0069] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway;
[0070] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway.
[0071] and a hydraulically operated tool
[0072] wherein the hydraulically operated tool is configured to be
actuated by fluid flowing through the downhole cutting tool.
[0073] The hydraulically operated tool may be configured to be
actuated by fluid flowing through the first and/or second flow
pathway through the cutting tool body.
[0074] The switching mechanism may be actuated by a set-down weight
and/or a drop ball.
[0075] Preferably the switching mechanism may be operable to
control the opening of the first and/or second fluid flow pathway
in response to an axial force.
[0076] The switching mechanism may be configured to selectively
open one of the first or the second fluid flow pathways in response
to an axial force.
[0077] The hydraulically actuated downhole tool may be selected
from a drill, mill, packer, bridge plug, hydraulic disconnects,
whipstock, hydraulic setting tools or perforating gun.
[0078] Embodiments of the fourth aspect of the invention may
include one or more features of the first, second or third aspects
of the invention or their embodiments, or vice versa.
[0079] According to a fifth aspect of the invention there is
provided a tool string comprising a downhole cutting tool
comprising:
[0080] a tool body;
[0081] a first flow pathway through the tool body;
[0082] a switching mechanism configured to open a second flow
pathway through the tool body and;
[0083] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway.
[0084] and a hydraulically operated tool;
[0085] wherein the hydraulically operated tool is configured to be
actuated by fluid flowing through the downhole cutting tool.
[0086] Preferably the switching mechanism is configured to open a
second flow pathway through the tool body in response to an axial
force.
[0087] The cutting mechanism may be configured to be actuated in
response to fluid flow in the second fluid flow pathway.
[0088] The cutting mechanism may be configured to be actuated in
response to fluid flow above a threshold flow rate in the second
fluid flow pathway.
[0089] Embodiments of the fifth aspect of the invention may include
one or more features of the first to fourth aspects of the
invention or their embodiments, or vice versa.
[0090] According to a sixth aspect of the invention there is
provided a tool string comprising a downhole cutting tool
comprising:
[0091] a tool body
[0092] a first flow pathway through the tool body;
[0093] a second flow pathway through the tool body;
[0094] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway;
[0095] a mechanism configured to selectively open one of the first
or the second fluid flow pathways in response to an axial force;
and
[0096] a drill tool;
[0097] wherein the drill tool is configured to be actuated by fluid
flowing through the cutting tool body.
[0098] The drill tool may be configured to be actuated by fluid
flowing through the first and/or second flow pathway through the
tool body of the cutting tool.
[0099] Embodiments of the sixth aspect of the invention may include
one or more features of the first to fifth aspects of the invention
or their embodiments, or vice versa.
[0100] According to a seventh aspect of the invention there is
provided a method of operating a downhole cutting tool
comprising:
[0101] providing a downhole cutting tool comprising
[0102] a tool body;
[0103] a first flow pathway through the tool body;
[0104] a second flow pathway through the tool body;
[0105] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway and
[0106] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway;
[0107] opening the second fluid flow pathway;
[0108] pumping fluid through the second flow path to actuate the
cutting mechanism.
[0109] The method may comprise opening the second fluid flow
pathway by actuating the switching mechanism. The method may
comprise actuating the switching mechanism by providing an axial
force. The axial force may be a set-down weight or a drop ball.
[0110] The method may comprise actuating the cutting mechanism by
pumping a fluid flow into the second fluid flow pathway. The method
may comprise rotating the tool whilst the cutters are deployed to
cut the casing. The method may comprise cutting the casing by
rotating a tool string connected to the downhole tool.
[0111] The method may comprise monitoring the fluid pressure
circulating through the downhole tool. The method may comprise
deactivating the cutting mechanism based on the monitored fluid
pressure level circulating through the downhole tool.
[0112] The method may comprise monitoring the force required to
rotate the cutting mechanism.
[0113] The method may comprise actuating the cutting mechanism by
rotating the cutting mechanism to cut the casing. The cutting
mechanism may be rotated by rotating a tool string connected to the
downhole tool.
[0114] The method may comprise monitoring the force required to
rotate the cutting mechanism.
[0115] Embodiments of the seventh aspect of the invention may
include one or more features of any of the first to sixth aspects
of the invention or their embodiments, or vice versa.
[0116] According to an eighth aspect of the invention there is
provided a method of operating a tool string in a wellbore tubular
comprising:
[0117] providing a tool string comprising a downhole cutting tool
comprising:
[0118] a tool body;
[0119] a first flow pathway through the cutting tool body;
[0120] a second flow pathway through the cutting tool body;
[0121] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway;
[0122] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway; and
[0123] and a drill tool;
[0124] actuating the drill;
[0125] opening the second fluid flow pathway and
[0126] pumping fluid into the second fluid flow pathway to actuate
the cutting mechanism.
[0127] The method may comprise opening the second fluid flow
pathway subsequent to actuating the drill. The method may comprise
closing the first fluid flow pathway. The method may comprise
actuating the drill by passing fluid through the first and/or
second flow pathway through the cutting tool body.
[0128] The method may comprise actuating the switching mechanism by
providing an axial force. The axial force may be a set-down weight
or a drop ball.
[0129] Embodiments of the eighth aspect of the invention may
include one or more features of any of the first to seventh aspects
of the invention or their embodiments, or vice versa.
[0130] According to a ninth aspect of the invention there is
provided a method of actuating a downhole tool on a tool string
comprising:
[0131] providing a tool string comprising:
[0132] a downhole cutting tool comprising:
[0133] a tool body;
[0134] a first flow pathway through the tool body;
[0135] a second flow pathway through the tool body;
[0136] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway and
[0137] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway; and
[0138] a downhole tool;
[0139] lowering the tool string into the wellbore;
[0140] pumping fluid through the first flow pathway to actuate the
downhole tool.
[0141] The method may comprise actuating the switching mechanism to
open the first flow pathway. The method may comprise actuating the
switching mechanism to close the second flow path.
[0142] The tool may be selected from hydraulically actuated
downhole tools including a drill, mill, packer, bridge plug,
hydraulic disconnects, whipstock, hydraulic setting tools or
perforating gun.
[0143] Embodiments of the ninth aspect of the invention may include
one or more features of any of the first to eighth aspects of the
invention or their embodiments, or vice versa.
[0144] According to a tenth aspect of the invention there is
provided a method of dressing off a cement plug and cutting a
wellbore tubular comprising:
[0145] providing a tool string comprising a downhole cutting tool
comprising:
[0146] a tool body;
[0147] a first flow pathway through the tool body;
[0148] a second flow pathway through the tool body;
[0149] a cutting mechanism configured to be in fluid communication
with the second fluid flow pathway and
[0150] a switching mechanism operable to control the opening of the
first and/or second fluid flow pathway; and
[0151] a drill tool;
[0152] lowering the tool string such that the drill is located on a
cement plug;
[0153] actuating the drill;
[0154] repositioning the tool string in the tubular at a desired
depth; and
[0155] actuating the cutting mechanism to cut the tubular.
[0156] The switching mechanism may be configured to selectively
open one of the first or the second fluid flow pathways in response
to an axial force.
[0157] The method may comprise actuating the drill by passing fluid
through the first and/or second flow pathway through the cutting
tool body.
[0158] The method may comprise actuating the cutting mechanism
opening the second fluid flow pathway and pumping fluid into the
second fluid flow pathway. The method may comprise closing the
first fluid flow pathway.
[0159] Embodiments of the tenth aspect of the invention may include
one or more features of any of the first to ninth aspects of the
invention or their embodiments, or vice versa.
[0160] According to an eleventh aspect of the invention there is
provided of actuating a downhole cutting tool on a tool string, the
method comprising:
[0161] providing a downhole cutting tool on a tool string, the
cutting tool comprising
[0162] a tool body;
[0163] a first flow pathway through the tool body;
[0164] a second flow pathway through the tool body;
[0165] a cutting mechanism configured to be actuated in response to
fluid flow in the second fluid flow pathway and
[0166] a switching mechanism configured to control the opening of
the first and/or second fluid flow pathway in response to an axial
force;
[0167] setting down a weight on the tool string;
[0168] pumping fluid into the second fluid flow pathway to actuate
the cutting mechanism.
[0169] Preferably the switching mechanism comprises a mandrel.
Preferably the mandrel is axially moveable in the tool body.
[0170] The method may comprise transmitting the set down weight to
the mandrel to move the mandrel axially in the tool body.
[0171] Embodiments of the eleventh aspect of the invention may
include one or more features of any of the first to tenth aspects
of the invention or their embodiments, or vice versa.
[0172] According to a twelfth aspect of the invention there is
provided a method of actuating a downhole cutting tool on a tool
string, the method comprising:
[0173] providing a downhole cutting tool on a tool string, the
cutting tool comprising
[0174] a tool body;
[0175] a first flow pathway through the tool body;
[0176] a second flow pathway through the tool body;
[0177] a cutting mechanism configured to be actuated in response to
fluid flow in the second fluid flow pathway and
[0178] a switching mechanism comprising a ball seat configured to
control the opening of the first and/or second fluid flow
pathway.
[0179] The method may comprise releasing an actuating ball in the
tool string to engage the ball seat.
[0180] Embodiments of the twelfth aspect of the invention may
include one or more features of any of the first to eleventh
aspects of the invention or their embodiments, or vice versa.
BRIEF DESCRIPTION OF THE DRAWINGS
[0181] There will now be described, by way of example only, various
embodiments of the invention with reference to the drawings, of
which:
[0182] FIG. 1A is a longitudinal sectional view through the
downhole tool in first operational mode according to a first
embodiment of the invention
[0183] FIG. 1B is an enlarged view of a section of the downhole
tool of FIG. 1A;
[0184] FIG. 1C is an enlarged view of the piston of the embodiment
of FIG. 1A;
[0185] FIG. 1D is an enlarged view of the pivot arm of the
embodiment of FIG. 1A
[0186] FIG. 2A is a longitudinal sectional view through the
downhole tool in a second operational mode according to an
embodiment of the invention;
[0187] FIG. 2B is an enlarged view of a section of the downhole
tool of FIG. 2A;
[0188] FIG. 3A is a longitudinal sectional view through the
downhole tool in a cutting mode according to an embodiment of the
invention;
[0189] FIG. 3B is an enlarged view of a section of the downhole
tool of FIG. 3A;
[0190] FIG. 4 is a longitudinal view of the downhole tool of FIG.
1A according to an embodiment of the invention.
[0191] FIG. 5A is a sectional view of a downhole tool in first
operational mode according to an embodiment of the invention.
[0192] FIG. 5B is an enlarged view of a section of the downhole
tool of FIG. 5A;
[0193] FIG. 6A is a longitudinal sectional view through of the
downhole tool of 5A in a cutting mode according to an embodiment of
the invention;
[0194] FIG. 6B is an enlarged view of a section of the downhole
tool of FIG. 6A;
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0195] FIGS. 1A, 2A and 3A are longitudinal sectional views of a
downhole tool in accordance with a first embodiment of the
invention in different phases of operation.
[0196] FIG. 1A is a longitudinal section through the downhole tool
10. The downhole tool 10 has an elongate body 12 and a mandrel
14.
[0197] A first end 14a of the mandrel 14 is configured to be
coupled to an upper tool string such as a drill string (not shown).
The second end 14b of the mandrel is axially movably mounted in the
body 12.
[0198] A first end 12a of the body 12 surrounds a portion of
mandrel 14. The second end 12b of the body is configured to be
coupled to a lower tool string such as a drill string (not shown).
The lower tool string may be connected to downhole tool located
further downhole. The second end 12b of the body is designed for
insertion into a downhole tubular first.
[0199] The mandrel 14 is configured to be axially moveable in the
body and is held in a first position by sheer screws 16. The tool
body 12 comprises a cutting mechanism 18 configured to deploy
knifes 20 to cut the casing.
[0200] FIG. 1B shows an enlarged view of area A-A'' of FIG. 1A. As
shown in FIG. 1A the cutting mechanism 18 comprises a plurality of
knives 20 disposed circumferentially around the tool body 12. (One
knife 20 is shown in FIGS. 1A and 1B). The knives 20 are rotatably
mounted on pivot 22, best shown in FIG. 1D, and are configured to
move between a storage position where the knives are retracted
shown in FIG. 1A and an operational position where the knives are
deployed shown in FIGS. 3A and 3B.
[0201] The mandrel 14 has a central bore 30 which is closed at the
second end 14b. At the second end 14b of the mandrel are located a
first set of ports 32 and second set of ports 34. The first and
second sets of ports are axially separated from one another. Ports
32 are in fluid communication with channels 32a in the mandrel
14.
[0202] FIGS. 1B and 10 shows a piston 40 which is axially movably
mounted in the body 12. The piston 40 is configured to move axially
between a first position shown in FIG. 1A and second position shown
in FIG. 3A. Although it is shown to move between a first and second
position, intermediate positions may be selected. The piston 40
comprises a piston sleeve 42. The piston sleeve 42 has a first
shoulder 44. Side 44a of shoulder 44 is configured to engage a
pivot arm 28 connected to the cutting knives 20, best shown in FIG.
1D. In the first mandrel position the position of the first
shoulder 44 hinders the rotation of the pivot arm 28 and maintains
the knives in a retracted position.
[0203] The piston 40 has an inlet nozzle 50 to a central bore 52
which extends through the piston 40. Ports 54 extend into the
central bore 52 of the piston.
[0204] The shoulder 44 is configured to minimize the maximum
cutting OD (sweep) of the knives when cutting. Side 44b of shoulder
44 is configured to stop the piston 40 at a set cutting OD (Sweep).
The side 44b of shoulder 44 may be configured to stop the piston 40
by engaging with a shoulder 47 on the tool body at a set cutting
outer diameter sweep. The maximum cutting OD may be adjusted. The
maximum cutting OD may be adjusted by changing the position of the
sleeve 42 on the piston 40. The sleeve is threaded attached to the
piston 40 and the maximum cutting OD can be adjusted by rotating
the sleeve. The sleeve position is secured in position by set
screws 58. Alternatively, or additionally a screw may be provided
that limits the amount the sleeve can be adjusted (not shown).
[0205] The piston 40 comprises a shoulder 60. Shoulder 60 is
configured to engage the pivot arm 28 connected to the cutting
knives 20 and to pivotally move the knives 20 between a knife
storage position shown in FIG. 1A and an operational position shown
in FIG. 3A when a fluid pressure is applied to piston 40.
[0206] The mandrel 14 is held in a first position relative to the
body 12 by shear screws 16. The mandrel is configured to move from
the first position shown in FIG. 1A to a second position shown in
FIG. 2A.
[0207] In the first mandrel position a first fluid flow pathway
through the tool is open. The first pathway consists of channels
32a on the mandrel 14 in fluid communication with a bypass channel
38. The bypass channel 38 is in fluid communication with ports 54
on the piston 40.
[0208] In a first mandrel position the ports 32 align with ports 33
and on the tool body. Fluid that flows through ports 32 and 33
flows into the annular space which may aid in the removal of
cutting and/or debris from cutting and/or drill sites.
[0209] During normal circulation mode, fluid flows through a first
flow pathway in the tool and may actuate and/or control another
tool located further downhole on the tool string.
[0210] Fluid flowing through the upper tool string first flows
through the first flow pathway then through bore 30 of the mandrel.
Fluid flows through bore 30 through channels 32a into the bypass
channel 38. The flow continues through ports 54 on the piston 40
into the bore 52. The fluid flows in the inner bore of the tool
string and may be used to actuate at least one downstream hydraulic
tool such as a drill, packer or bridge plug (not shown). Some fluid
flows through ports 32 and 33 into the annular space.
[0211] In the first mandrel position the ports 34 are blocked by
port valve 35 which prevents flow from acting on the piston sleeve
to actuate the cutter mechanism 18.
[0212] In the first mandrel position, the tool 10 can be rotated on
the work string and fluid may be pumped through this first pathway
without actuating the cutting mechanism and deploying the knives.
This may facilitate the actuation of a downstream tool to enable
multiple tasks to be performed in once the tool is deployed
downhole without requiring the tool to return to surface.
[0213] Flow through the tool may control the actuation of a
downstream tool such as a drill or mill and may enable cement
dressing off of a cement plug prior to the casing being cut by the
cutting mechanism.
[0214] By proving a first pathway which bypasses the actuating of
the cutting mechanism in the first mandrel position the tool may
allow a high fluid flow rate to be pumped through the tool. The
tool may also allow the transfer torque to a downstream tool such
as a drill bit or mill without actuating the cutting mechanism.
FIG. 4 shows a longitudinal view of the tool in circulation
mode.
[0215] In order to move the mandrel from a first position to a
second position an axial load is applied to the mandrel 14. The
axial load may be provided by a set down weight or hydraulic
pressure. In this example the axial load is provided by a set-down
weight which moves the mandrel from the first axial position shown
in FIG. 1A to a second axial position shown in FIG. 2A.
[0216] The mandrel 14 is configured to be moved within the body 12
to a second position as shown in FIG. 2A and 2B. The mandrel is
held in the second position by spring activated keys 19 located in
an internal surface of body 12 engaging with grooves 19a located on
the outer surface of the mandrel.
[0217] FIGS. 2A and 2B show the mandrel in the second position
where the mandrel 14 closes the first pathway and opens a second
pathway. The mandrel 14 is moved axially such that ports 32 are not
aligned with ports 33 on the body preventing fluid flow from the
bore 30 into the annular space. The channels 32a are blocked by
port valve 35 and are no longer in fluid communication with the
bypass channel 38. The ports 34 on the second end 14b of the
mandrel are moved through port valve 35 into chamber 62 in the body
12.
[0218] The piston 40 is biased in a direction X by spring 64 as
shown in FIG. 2A. In this example the spring 64 is a compression
spring. However, it will be appreciated that any spring,
compressible member or resilient member may be used to bias the
sleeve in a first position.
[0219] The spring force acting on the piston provided by spring 64
in direction X maintains shoulder 44 in contact with pivot arm 28
and prevents pivot arm 28 from rotating and deploying the knives
20.
[0220] FIGS. 3A and 3B show the actuation of the cutting mechanism
when the mandrel in is the second position. Fluid is pumped into
the tool string and flows through the second pathway to actuate the
cutting mechanism.
[0221] Fluid passes through the second pathway. Fluid flows through
bore 30 of the mandrel into the chamber 62 via ports 34 on the
mandrel 14. The chamber 62 is in fluid communication with an
axially moveable restrictor assembly 66. The flow resistor assembly
66 has an inlet nozzle 68, a bore 70 and an outlet 72. The inlet
nozzle 68 is configured to introduce a pressure difference in the
fluid upstream of the inlet nozzle 68 and the fluid downstream of
the inlet nozzle 68.
[0222] The fluid flows through the nozzle 68 of the flow restrictor
assembly 66. The nozzle 68 is dimensioned to provide a resistance
to flow. When the fluid pressure applied to the nozzle 68 it moves
the flow resistor assembly 66 in direction Y as shown in FIG. 3A.
The outlet 72 of flow restrictor assembly 66 is aligned and/or
seated on inlet nozzle 50. When the fluid pressure applied to the
nozzle 68 is sufficient to overcome the spring force of spring 64
the flow restrictor assembly 66 and piston 40 are moved towards
second end 12b of the downhole tool, shown as direction Y in FIG.
3A.
[0223] The flow resistor assembly 66 may be adjusted to stop at
selected position after travelling a predetermined distance in
direction Y. When the flow resistor assembly 66 stops at this
selected position the outlet 72 of flow restrictor assembly 66 will
not be aligned and/or seated in inlet nozzle 50. Flow will bypass
the smaller nozzle 68, and will flow through the larger sleeve
inlet nozzle 50. This may provide a pressure change when the knives
are at a certain cutting OD (sweep) and provide an indication that
the knives are deployed and/or the cut has been made.
[0224] Movement of the piston 40 and sleeve 42 in direction Y
axially moves shoulder 60 to engage and move pivot arm 28 connected
to the cutting knives 20. The knives 20 are moved to an operational
position to allow the cutting of a casing shown in FIG. 3A.
[0225] The pivot arm 28 has a slot 29 (best shown in FIG. 1D) which
prevents the pivot arm impacting the sleeve when the knife is
rotated to an extended position.
[0226] To retract the knives 20, the fluid flow through the second
pathway is reduced. The fluid pressure applied to nozzle 68 and/or
nozzle 50 is no longer sufficient to overcome the spring force of
spring 64 and the flow restrictor assembly 66, piston 40 and sleeve
42 are moved towards first end 12a of the downhole tool, shown as
direction X in FIG. 3A.
[0227] The movement of the piston 40 in direction X moves the
shoulder 60 to disengage with the pivot arm 28. Shoulder 44 engages
with the pivot arm 28 which rotates pivot arm 28 and retract the
knives 20.
[0228] The fluid pumped through the second pathway may be adjusted
to control the degree of deployment of the knives 20.
[0229] The tool and/or tool string may be rotated with the knives
deployed to cut the tubular. The tool can be rotated when the
knifes are in an operational or retracted position. The tool has a
spline that transfer the torque in both positions.
[0230] The tool described above may be provided with a plurality of
seals. Seals may be provided along the first and/or second pathway
to prevent fluid egress. Seals may be provided between the mandrel
and the tool body.
[0231] The above example described the switching between a first
mandrel position and a second mandrel position by applying an axial
force in the form of a set-down weight. However, an alternative
method applying an axial force is a ball-drop.
[0232] FIGS. 5A, 5B, 6A and 6B show an alternative design for
downhole tool 110. The tool comprises a ball seat 180 at end 114b
of mandrel 114. The ball seat 180 has first series of ports 182 and
a second series of ports 184 (shown best in FIG. 5B). The first
series of ports 182 are aligned with the first pathway. The first
fluid pathway is similar to the first fluid pathway described in
relation to FIG. 1A and 1B and will be understood from the
description of FIG. 1A and 1B above.
[0233] During normal circulation mode, the first fluid flow pathway
through the tool is open. The first pathway consists of first
series of ports 182 on the ball seat 180 which are in fluid
communication with a bypass channel 138. The bypass channel 138 is
in fluid communication with ports 154 on the piston 140.
[0234] Fluid flows through the first flow pathway and may actuate
and/or control a hydraulically operated tool located further
downhole on the tool string.
[0235] Some flow may pass through the second series of ports 184 in
the ball seat and into the second flow path. The second flow path
is similar to the second fluid pathway described in relation to
FIG. 2A and 2B and will be understood from the description of FIG.
2A and 2B above. The second fluid pathway consists of series of
ports 184 on the ball seat 180 which are in fluid communication
with chamber 162. The chamber 162 is in fluid communication with
the cutting mechanism 118. However, during normal circulation mode
the flow through the second flow path is not sufficient to actuate
the cutting mechanism 118.
[0236] FIG. 6A and 6B show actuation of the cutting mechanism. To
actuate the cutting mechanism 118 a ball 190 is dropped in the bore
of the tool string and is carried by fluid flow through bore 130
until it is retained by the ball seat 180. Once the ball 190 has
engaged the ball seat 180 the ball 190 blocks ports 182 preventing
fluid flow in the first pathway. Fluid is directed though ports 184
into the chamber 162 and through the second pathway. The actuation
of the cutting mechanism is as described in relation to FIG. 3A and
3B and will be understood from the description of FIG. 3A and
3B.
[0237] In this example the mandrel is not axially moveable between
a first and second position. In this case the first series of ports
182 are always aligned with the first pathway and the second series
of ports 184 are always aligned with the second pathway.
[0238] Alternatively, and/or additionally, the mandrel and/or ball
seat may be axially movable in the tool body. The mandrel and/or
ball seat may be axially moveable when sufficient fluid pressure is
applied to the ball and ball seat providing an axial force on the
mandrel to move it to a second position. The mandrel and/or ball
seat when moved to the second position the second series of ports
are aligned with the second pathway.
[0239] During normal circulation mode, fluid flows through the bore
of the mandrel. The flow passes through the first flow pathway via
the series of ports and may actuate and/or control a hydraulically
operated tool located further downhole on the tool string.
[0240] To actuate the cutting mechanism a ball is dropped in the
bore of the tool string and is carried by fluid flow where its
retained by the ball seat. Once the ball has engaged the ball seat
it blocks the first series of ports preventing fluid flow in the
first flow pathway. The fluid pressure may act on the ball seat and
when sufficient fluid pressure acts on the ball seat the mandrel
and/or ball seat be axially movable to a second position in the
tool body. The mandrel and/or ball seat in the second position
uncovers a second series or ports which are in fluid communication
with the second fluid path way. Subsequent fluid flow through the
second fluid flow pathway actuates the cutting mechanism disposed
in the second fluid flow pathway.
[0241] Throughout the specification, unless the context demands
otherwise, the terms `comprise` or `include`, or variations such as
`comprises` or `comprising`, `includes` or `including` will be
understood to imply the inclusion of a stated integer or group of
integers, but not the exclusion of any other integer or group of
integers. Furthermore, relative terms such as", "lower","upper,
"up" "down" and the like are used herein to indicate directions and
locations as they apply to the appended drawings and will not be
construed as limiting the invention and features thereof to
particular arrangements or orientations. Likewise, the term "inlet"
shall be construed as being an opening which, dependent on the
direction of the movement of a fluid may also serve as an "outlet",
and vice versa.
[0242] The invention provides a downhole cutting tool. The tool
comprises a tool body, a first flow pathway and a second flow
pathway through the tool body. The tool also comprises a cutting
mechanism configured to be in fluid communication with the second
fluid flow pathway and a switching mechanism configured operable to
control the opening of the first and/or second fluid flow
pathway.
[0243] The present invention obviates or at least mitigates
disadvantages of prior art downhole tools and provides a robust,
reliable and compact downhole cutting tool suitable for actuating
multiple downhole tool and cutting a casing in a single trip.
[0244] The invention enables multiple downhole operations to be
performed on the same downhole trip, which normally would require
at least two separate trips. The invention allows sufficient fluid
flow to be pumped through the tool to actuate tools on the tool
strings further downhole without uncontrolled actuation of the
cutting tool.
[0245] The invention allows the selective actuation of different
tools on the same tools string. This may facilitate the controlled
actuation of downhole tools such as drills and mills which require
high flow rates on the same tool string as a casing cutter tool
which requires a lower fluid flow rate.
[0246] This may facilitate the actuation of a drill to dress-off a
cement plug and the subsequent activation of the cutting tool to
cut the casing in a single downhole trip. The invention avoids the
simultaneous and/or accidental actuation of the downhole tools on
the tool string. The downhole cutting tool has improved
productivity and efficiency, and is capable of reliably performing
multiple downhole operations once deployed downhole.
[0247] The foregoing description of the invention has been
presented for the purposes of illustration and description and is
not intended to be exhaustive or to limit the invention to the
precise form disclosed. The described embodiments were chosen and
described in order to best explain the principles of the invention
and its practical application to thereby enable others skilled in
the art to best utilise the invention in various embodiments and
with various modifications as are suited to the particular use
contemplated. Therefore, further modifications or improvements may
be incorporated without departing from the scope of the invention
herein intended.
* * * * *